My Geography teacher has started an experiment which involves me writing about what I have learnt in my lessons and about any geographical news that interests me. My Geography teacher is also going to write a blog about what she teaches me (and therefore what I should have learnt!) and hopefully the two blogs will match up. The idea is that this will not only help me to consolidate what I learn but that it will also help fellow students do the same and keep up to date with current issues.

Friday, 13 May 2011

UWE lectures

I realise that many of you were not as fornuate as me and able to attend the two sessions yesterday afternoon run by two lecturers from UWE and, because they were so good, I thought I would share with you some of the things that were discussed.......

Climate Change and River Management:

What is climate change?
Before you can understand the impacts climate change is expected to have on rivers, a basic understanding of what climate change is, is required. Climate change refers to any long-term change in the statistical distribution of weather patterns over periods of time that can range from decades to millions of years; although it is most commonly used in reference to the increase in the average surface temperature of the earth over the recent decades and that which is predicted in the foreseeable future. Much of the work on climate change and its impacts on rivers is based on estimates as it is very hard to predict the future climate as it is dependent on a wide variety of things - although most importantly carbon dioxide emissions. Despite this uncertainity, central estimates have been produced for changes that are expected to occur within the UK, within the next 30 years.....

Increase in the average summer temperatures of 3-5 degrees Celcius

10-30% increase in the average levels of precipitation experienced during the winter

There will be spatial variations though, from these intermediate values. For example, some areas of the UK are likely to experience a decrease in the mean winter precipitation level whilst others are expected to experience a 50% increase.

What is River Management?
River management is any action that includes intentional intervention by humans into the way that river systems funtion. This includes:
- Managing the quantity of water flowing through the channel ---> flooding, droughts, freshwater supply, reservoirs and flow regime modification
- Managing the stability of river channels ---> rivers are unstable and constantly change due to the processes of erosion and deposition and this threatens to cause major, and very costly damage, to infrastructure
- Managing water quality ---> pollution from littering, industry, sewage, sediment and agriculture (eutrophication)
- Managing the physical quality of the river ---> management of ecosystems to maintain and maximise biodiversity

Although managing water quality and biodiversity etc are considered when it comes to river management, its primary aim is to reduce the flood risk. Reducing the flood risk is a big problem for England and Wales as around 4 million people and £200 billion worth of infrastructure are a risk of flooding. At present, even though we spend roughly £800 milliom per year on flood and coastal defences, we experience £1,400 million of damage. Worryingly, this is the damage caused and the costs associated with current sea levels, temperatures and precipitation levels and so the impacts of climate change are likely to provoke a sharp increase in those at risk and the costs involved with reacting to the risks. It has been estimated that, due to the expected increase in the recurrence and magnitude of floods, that the costs of damage done by them could rise from £1,400 million a year to anything up to £20,500 million over the next 70 years if no further action is taken.

So, how is climate change likely to affect the flood risk........
Flood risk is the balance between the conveyance capacity and the amount of water that is actually trying to move through the channel and it is this balance that climate change threatens to disrupt, thereby increasing the flood risk.

Conveyance capacity is, in very simple terms, the amount of water that can fit in the channel and so when this level is exceeded by the actual amount of water trying to fit in the channel, flooding occurs. Due to increased precipitation levels, climate change is predicted to increase the flow. This means that there is more water trying to pass through the river and so a higher probability that this volume will exceed conveyance capacity and therefore result in flooding. A study carried out on a small section of the River Wharfe in Yorkshire, which was based on this idea, concluded that increased flows by 2050, provoked by climate change, would result in a 12.2% rise in the area flooded by a 1 in 0.5 year return flood.

An increase in flow would provoke an increase in sediment and the relationship between the two can be descirbed as being non - linear (for exmaple, in the River Eden, in Cumbria, an increase of 4.2% in precipitation would lead to a 90% increase in the amount of sediment transported). The amount of sediment within a river is further being increased by urbanization. Although urbanization means that there is less bare surfaces, like soil, for sediment to be sourced from; because urbanization produces flashier rivers, as the increase in impermeable surfaces means the water enters the channel quicker; when the water reaches the channel it has more energy and so a greater erosive ability - which results in excess erosion and so therefore more sediment in the river. This decreases the conveyance capacity of the river and so the volume of water that can flow through the channel, before it reaches and exceeds bankfull capacity, is reduced. This relationship between sediment and flow was also tested on the River Wharfe and it concluded that a reduction in the size of the channel, caused by sediment deposition over two years would increase the flood risk by 5.7%.

Rivers are not stable and constantly change which makes it increasingly hard to make predictions in sediment dynamics and how rivers will change in the future due to climate change. To aid the development of rough predictions, cellular catchment evolution models have been created, like CAESAR (Cellular Automaton Evolutionary Slope and River model). CAESAR works by dividing drainage basins into 10m by 10m grid cells and then uses the height above base level and basic information on the river channel and whether or not one is present, to generate a virtual model of the landscape. CAESAR can then simulate the morphological changes in river catchments, on a flood by flood basis, over periods up to several thousands of years. This was used on the River Eden and clearly showed that the predicted increase in flows would increase the sediment yield and this would directly increase the amount of sediment deposited thereby result in a significant increase in the flood risk. So, for example, for the town of the Carlise this means that increased deposition reduces the conveyance capacity and so increases the flood risk.

Climate change will also affect rivers in other ways too:

More fine sediment will be depoisted in the river beds and thereby smother the natural environment used by fish for spawning

Increased sediment flow will block out the sunlight and lead to the death of many organisms

Increase in water temperatures will reduce the concentration of dissolved oxygen in the water and so will kill of many organisms. Also, the warmer conditions will encourage the growth of tropical species which will result in many of our native species being outcompeted

All of this just takes into account the impacts of climate change on rivers, but urbanization too, imparticular with reference to landuse change, will alter the flows into a river. As populations continue to grow this is going to become more of an issue - especially in areas like Bangladesh whose flood risk is affected by the deforestation in Nepal for fuelwood or in areas like India who are likely to see rapid urbanization over the coming decades.

There are solutions to these problems that we are likely to face, like strategic tree planting in the form of tree belts which can be planted to specific places in drainage basins to trap sediment, increase the interception store and therefore reduce the amount of water entering channel and increase the time taken for water to enter the channel. This example of soft engineering is very sustainable as it will continue to work even if climate change provokes increases in flows into a river.

So, in conclusion, climate change is likely to increase the flood risk by increasing the flow and thereby the sediment yield of the river whilst causing degradation of the physical habitat and water quality. This means that more needs to be done, and perhaps a different approach taken, to try and reduce the flood risk - so, if you are interested in a career related to river management and flood control there are likely to be lots of available jobs, in this field, in the near future!

Coastal Management in Bridgewater Bay:

What is the coast?
The coast is the region of mutual interaction between terrestial and marine environments and is extremely valuable in terms of as a defence, a habitat and a resource (industry and tourism). 50% of the worlds population live within 2km of the coast mainly due to the above reasons, its historical importance, for trade, climate, food and the flat and fertile land associated with it and so coasts are therefore important to manage and with rising sea levels and growing populations, the need to do so is only increasing.

Sea level rise is not a new thing though and has happened throughout history......

18,000 years ago the last glacier was at its maximum extent and so sea level was 140m lower than at present

Initially the melting of the ice was rapid and so sea level rose rapidly but it gradually started to slow

4000 years ago sea level reached its present day level

This melting of ice has had significant impacts on coastal processes and landforms but its hasnt been until recently that people are becoming increasingly concerned by centimetre rises in sea level - why is this? Perhaps the biggest reason is us ourselves. People are now living closer and closer to the coast and as populations grow further in the developing world, more and more are going to be forced to live on marginal lands. Also, the building of infrastructure has restricted the migration of landforms in response to changes in sea level and therefore reduced the development of natural defences like salt marshes and sand dunes.

In terms of the South West, we are very prone to coastal flooding as much of the land lies below sea level already (and I think, that this area will increase not only due to rise in sea level but also isostatic readjustment in Scotland which is causing this part of the world to sink slightly). This means that coastal management is required to ensure that those living here are protected.

The question; would you rather live behind a sea wall or a sand dunes system was asked - you can make your own mind up on which you would prefer - but the class I was in was split. Many said that they would rather be protected by a sea wall but were they wrong........

Firstly, lets go over the basics of sand dunes and beaches. Beaches and dunes are linked and wind energy can modify beaches to create specific landforms like sand dunes which are created by aeolian sediment transport.
Different factors are required for the formation of sand dunes including:

an area to accomodate them

vegetation

onshore winds

sediment supply

shallow sloping beach

high tidal range

The sediment needed for dunes is transported via saltation which is when the sand is picked up and moved forward by the wind and then pushed further back by the land. This sand is transported from the intertidal zone unitl the saltating sediment reaches the back of the beach.

Sand dunes are such a good coastal defence as, unlike a sea wall, they are not a static sea defence (although due to human influences provoking coastal squeeze they are being forced to be more static than they would like) and so change to new conditions. New such conditions can occur due to storm surges. Storm surges are generated by tropical storms as the low pressure system and winds associated with them, provoke a large, but temporary, rise in sea level. This is why they have the capacity to cause extensive flooding over coastal lowlands. The average storm surge in the UK, adds an additional 1.45metres in height to that of the high tide and therefore much of the UK, especially around this part of the country, is suseptible to flooding. If you then factor in the possilbe impacts of climate change on sea levels and the frequency and severity of storms, this is likely to become more and more of a prominant issue in the not too distant future.

In relation to sea level rise, the IPCC predict a :-

0.10m - 0.30m rise by 2030

0.50m rise by 2050

In terms of protecting against storm surges, sea walls will be able to cope to a certain extent, but it is both too costly, unsightly and unsustainable to keep raising the height of sea walls to keep up with rising sea levels. Sea walls are clearly a static form of defence that cannot adapt to changing conditions but beaches can - which is one of the reasons they can form such a good, natural, sea defence. Beaches can change shape in response to changing conditions and so do sand dunes. Beaches will adjust to accomodate for larger than normal waves. High energy conditions flatten the beach and so give it a dissipative profile that provokes waves to break earlier and disperses their energy. This means that less of the waves intitial energy reaches the back of the beach and so its erosive ability is reduced. High energy conditions do not last forever and so beaches and sand dunes, during low energy conditions, are able to rebuild and readjust themselves. This process involves the increase in the onshore transportation of sediment which causes the beach to build up and adopt a reflective profile.

Beaches and sand dunes, imparticular, are crucial for the protection of the of coasts over the next 100 years and are by far the most sustainable option. Not only do they cost alot less than many hard engineering options, they create rare and vital habitats that provide a home for a diverse range of species, both plants and animals, but they are also, and perhaps most importantly, able to adapt to changes in conditions that we are going to face in the not too distant future. The development of dune systems sometimes needs a helping hand. For example, in Bridgewater Bay, the beach is becoming very muddy and consists of very fine grain which is not ideal for sand dunes and so beach nourishment is required to feed the dunes. However this is significantly less costly than building a huge sea wall. What option for coastal management further in the future than the next 100 years is best is unclear. Urbanization, the encroachment of developments onto the coastline and our attempts to fix sand dunes into there location means that sand dunes will not offer a sustainable and effective coastal defence option for ever. Depsite the fact that they can adapt to changes in the energy levels and height of the sea/waves, they are unable to adapt to us changing surfaces and restricting their movement. Coastal squeeze is one of the largest threats to sand dunes and their development as the building of housing developments and sea walls etc is preventing sand dunes from migrating, which allows them to adapt to new conditions. Instead anthropogenic influences on the sand dunes have the potential to turn the dunes into an almost static form of defence which threatens to halt their development and lead to their destruction. This is why land use management is more crucial than ever (this implies to rivers aswell). With the risks of coastal flooding and extensive erosion being so high, is it really a good idea to be building new developments right along the coast or by waterways. For example, think about Hinkley Point.........

............ with the predicted rises in sea levels generating a higher flood risk; is it really a good idea to further develop nuclear power here??? This is of course not the only example....... people love to live on floodplains or near the coasts which are the areas most prone to flooding and not only does this increase and worsen the secondary impacts of flooding but it also increases the chance of flooding happening in the first place. Therefore, in the near future, greater consideration into landuse management is going to be needed to help reduce the risks of coastal flooding.

So, in conclusion, opting for natural sea defences like sand dunes are by far the most sustainable option in the near future as they are able to adapt and cope with changing conditions but this approach needs to be accompanied by landuse management to further reduce the risk of flooding and lengthen the time for which sand dune systems can offer a sustainable and effective method of managing and reducing the risk of coastal flooding.

This is just a summary of what we got taught and so only really covers the basics and is no way near as good as actually participating in the lectures yourself - but unfortunately many of you were unable to attend and so you will have to put up with my explanation instead..........

I hope the revision is going well - if there is anything I can do to help, via this blog, please don't be afraid ask. I have had lots of requests surrounding the topic of rejuvenation in rivers and, as it is a tricky topic which took me a long time to get my head around, I am going to try and write a summary post about either later tonight or tomorrow...........

Geography Films

My Geography teacher is always reminding my class that watching (geography related) films can contribute to the 3 hours of reading time we are supposed to do each week. On both her blog and the Facebook page there are lists of recommended films and so I thought I would start to watch some of them and write a review on them from a student's perspective. If I would recommeded them to a fellow student then I will add the film to my own list below.......

- THE AGE OF STUPID (great film to watch for the energy module as it talks about climate change, energy consumption and production via some interesting case studies)

- THE COVE (this film is very thought provoking and presented the issues surrounding the dolphin trade - before watching this I didn't know a lot about the issue, especially the scale of it in Japan, and it left me feeling very shocked that something like this still exists today in such a developed country)

-ENCOUNTERS AT THE END OF THE WORLD (a great documentary with some simply stunning footage and interesting interviews that collectively provide an insight into life in Antarctica and the important research that is taking place)

-THE CONSTANT GARDENER (a rather sad story about how a drug company exploit the Kenyan population to allow them to test a new drug, despite the fact they know it has harmful side effects - good film for development and globalisation)

- ERIN BROCKOVICH (a good film that presents the negative impacts of the natural gas industry and the extent to which large companies are prepared to go to, to cover this up)

- SLUMDOG MILLIONAIRE (provides an insight into the life of children living in the Indian slums - good film to watch for development)

- GANDHI (a biopic about the life of Gandhi with particular reference to his prominent role in India's struggle for freedom from colonial rule)

- CRY FREEDOM (set in South Africa and tells the true story of Biko and his friendship with a white liberal newspaper editor - good film to watch for development)

- THE PAINTED VEIL (set in China, in the 1920's, and explores the impact of a cholera outbreak on a village, including references as to how religious beliefs make containing cholera even more challenging)

- BLOOD DIAMOND (set amid the explosive civil war overtaking 1999 Sierra Leone; it explores many issues including those surrounding the diamond trade, supply of arms to rebels and child soldiers - good film to watch for development and globalisation module)- THE DAY AFTER TOMORROW (after the Larsen B ice shelf collapses, the thermohaline circulation shutdowns, provoking glacial inception in the northern hemisphere - a good film to watch and then point out the geographical/scientific mistakes!)

- GOODBYE BAFANA (follows the unlikely friendship that forms between Mandela and his prision officer - good for development and globalisation)

- INVICTUS (after 27 years imprisionment, Mandela becomes South Africa's first elected president and this film follows his bid to unite the country via the rugby world cup - good film for development and globalisation)

- DARFUR (a group of international journalists travel to a village in Darfur in search of evidence to persuade the UN that genocide has occured but are forced to live after the Janjaweed turn up and threaten to kill them.... a film to watch for either development and globalisation or the population module but be warned it is very graphic)

Geography Books

I am a bit of a bookworm and often prefer reading a good book to watching a film and so (like I am doing with the Geography films) I am going to read some of the suggested books and write a review on them so I can comment on whether or not I think they are worth reading........

- AN INCONVENIENT TRUTH, Al Gore ( presents the issue of climate change and discusses how it has been caused and the impacts it is likely to have - well worth reading but if you prefer the film version is equally as a good)

- OUR CHOICE, Al Gore (this books follows on from An Inconvenient Truth by offering the solutions Al Gore thinks are required to solve the issue of Global Climate Change)

- THE BOY WHO HARNESSED THE WIND, William Kamkwamba and Bryan Mealer (tells the extraordinary true story of a Malawian teenager who overcame many obstacles to provide electricity and clean water for his village by capturing the energy in both the wind and the sun)

- BLOOD RIVER, Tim Butcher (tells the story of Tim Butchers quest to retrace the journey taken by H.M.Stanley in the 1870's. From this you get an insight into the history of the Congo and the factors that have effected its development - great book for the development and globalisation module as it provides an insight into the impact colonialism has had on Africa)

- GAIA, James Lovelock (presents the Gaia hypothesis which is the idea that the Earth functions as a living organism and so self-regulates to adapt to changing conditions - puts forward some very interesting ideas and really makes you think - it is worth a read!)

- THE REVENGE OF GAIA, James Lovelock (applies the Gaia hypothesis to global climate change - again an intriguing read which presents some interesting ideas and solutions to problems we are likely to face)

About Me

Whilst studying A-levels in Geography, Chemistry, Biology, Maths and History, I became completely fascinated by the Earth Sciences and found them particularly good for feeding my natural curiosity, providing answers to my never ending list of questions! Despite my relentless enthusiasm and frequent question asking, I was quite a quiet student in comparison to the rest of my class so my teacher asked me to start this blog as part of her experiment to test the benefits of incorporating social media into education. The aim was to find out if social networking can be a valuable educational tool and discover how much I actually learnt in lessons. It proved to be a huge success, for both myself and other students, with all my A-level notes still available for students use. I am currently at University studying BSc (Joint Honours) ‘Physical Geography with Oceanography’ and still asking way too many questions! In an attempt to continue to share my love for anything Earth Science-related, and to see if it can have the same benefits at Higher Education, I am trying to continue the blogging and use of social networking. I hope it proves to be a useful and interesting read!

The what, why and how of this blog.......

Hopefully you will have worked this out by now, but this blog is written from a student's perspective and, when combined with my teachers blog, should provide an insight into what I get taught - therefore what I should have learnt - in my Geography lessons. The idea is that this will make it a useful place to go to consolidate your learning; somewhere to go if you didn't quite understand something or missed a lesson. As well as this, posts will be written on anything of general geographical interest whether that be something currently in the news, anything related that I read or watch, anything I do or a topic that I just fancy finding out more about - all of this is designed to broaden our geographical knowledge. When it comes to revision I will try and write up as many notes as possible but it is unlikely that I will be able to cover everything so just let me know if there is anything you would like me to cover. So, thats what the blog is about (simply sharing, with anyone willing to read it, lots of geographical stuff that interests me!) and I am writing it because I tend to get a little enthusiastic about Geography and ask too many questions and so by channeling my interest in this way it will hopefully help you as much as it helps me!!! Whats the best way to use it? Well for starts reading/following the blogs and other resources is the only way you will benefit from them! Secondly, participate and get involved - comment on things, I am bound to get things wrong so correct me, you won't agree with everything I say so tell me what you think and perhaps even suggest things for me to read, watch or look into as I am always looking for new ways to extend my knowledge outside of the classroom. Geography is a discursive subject and, especially with human Geography, for the most part about forming/expressing opinions, so discuss the topics raised via the blogs etc. - trust me, its an easy way to learn!

I am now at University studying BSc (Joint Honours) Physical Geography with Oceanography - to keep my A-level notes separate I have started a new blog for current news and what I am learning in University - anything relevant I will also post on this blog, but please feel free to ask questions or requests posts! I hope students are still finding this a useful resource!

Disclaimer

'What I learnt in Geography this week.....' was created by, with content written by Vicki The Geography Student as part of an experiment conducted by Millie The Geography Teacher.

All posts published are my personal views, apart from where stated otherwise, and not those of the college I attended, my University or associated partners